The term urinary dysfunction encompasses both urinary incontinence, which can range from some leaking to complete loss of bladder control, and irritative voiding symptoms (symptoms triggered by the irritation of the tissues), including increased urinary frequency, increased urinary urgency, and pain upon urination. Obstruction of the bladder by an enlarged prostate is the typical reason for these symptoms initially; however, after therapy, these symptoms are typically caused by damage to the nerves and muscles that control urinary control.
Under normal circumstances, the urinary sphincters (bands of muscle at the base of the bladder and at the base of the prostate) remain tightly shut, preventing urine that’s stored in the bladder from leaking out. During urination, the sphincters are relaxed and the urine flows from the bladder through the urethra and out of the body.
In prostatectomy—the surgical removal of the prostate—the bladder is pulled downward and connected to the urethra at the point where the prostate once sat. If the sphincter at the base of the bladder is damaged during this process, some degree of urinary incontinence or leakage may occur. Nearly all men will have some form of leakage immediately after the surgery, but this will improve over time and with strengthening exercises. Most men regain urinary control within a year; approximately 1 in 10 men will have mild leakage requiring the use of 1 or more pads per day. Pelvic floor muscle training with a physical therapist can help. In the case where side effects are severe, an artificial urinary sphincter can be considered.
Radiation therapy is targeted to the prostate, but the bladder is next to the prostate and the urethra runs through the middle of the prostate, so both will receive some radiation. Fortunately these structures are fairly resistant to radiation therapy, and long-term leakage is rare (1 in 100). However, they can become irritated during and for months after radiation therapy, which usually manifests as a mild increase in urinary frequency and urgency. This can also manifest as nocturia, or waking up more at night to urinate. Nocturia is most common in the few weeks following radiation therapy. These side effects are uncommon after surgery; in fact, for men who have significant symptoms like frequency and nocturia due to prostate enlargement, surgery can actually lead to an improvement in urinary function by simultaneously treating both the prostate cancer and prostate enlargement.
There are a number of strategies for managing side effects from prostate cancer treatment.
Some form of urinary dysfunction is normal following initial therapy for localized prostate cancer. But it’s important to realize that not all symptoms are normal, and that some require immediate care. Continuing to work with your urologist to optimize your urinary function is an important part of your ongoing care. See When To Seek Help for a review of what to do if the symptoms do not improve or if they worsen over time.